Saw.



Patented Mar. 27, 1900. D. PHILLIPS.

SAW'.

(Applicaticn filed July 29. 1898 (No Mbdel.)

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* rrron PATENT DEWEY PHILLIPS, OF ARLINGTON, VERMONT;

SAW.

SPECIFICATION forniing part of Letters Patent No. 646,:37'3, dated Mr- 2`7, 1906.

I Application filed July 29,1898. Serial No. 687,167. (No model.)

To all whom, it may concern:

Be it known that I, DE EY PHILLIPS, a citizen of the United States, residing at East Arlington, in the county of Bennington and State of Vermont, have invented an Improvement in Saws, of which the followingis a specification.

In the manufacture of circular saws the middle portion of the saw has been reduced in thickness by grinding, so as to lessen the friction of the saw 'upon the Wood; but in use it is found that the rim of the saw is lable to become warm and to expand, and the middle portion of the saw not becoming warm causes the rim of the saw to become undulating by the expansion.

The present invention is made with reference to allowing the rim of the saw to expand if it becomes warm while in use and still retain its accurate shape as a plain fiat surface, and I also provide in the threats of the saw-teeth detachable throat-pieces having V- shaped grooved surfaces, so that curved cutting edges are formed by the throat-pieces, the object being to maintain uniformity in the width of the kerf and smooth surfaces upon the wood and receive the sawdust, so that the teeth may not be crowded in the kerf and the saw heated by friction,

In the drawings, Figure l is a side View showing a part of a circular saw, and Fig. 2 is a section at the line 2 2. Fig. 3 is a side View, and Fig. 4 a cross-section at the line et 4, showing the detachable threat-piece; and Fig. 5 is a section at the line 3 3 of Fig. 1.

The saw-plate is of any desired size and thickness, the outer portion 5 of the plate being maintained of the full thickness of the plate, and the inner portion 6, around the eyes 7, also being of full thickness, or nearly so. The intermediate portions of the plate are reduced in thickness, as shown at 8; but if these features only were made use of it would not be possible to maintain the edge portion of the saw perfectly true if it became heated. I therefore employ undulations 9 in the thinner portion of the saw, said undulations being radial, or substantially so, in order that such undulations may spring or yield to an expansion of the outer portion of the saw.

I prefer to make the undulations 9 radial, and according to the size of the saw these undulations can be more or less numerous, and they may be formed in the grinding up of the saw, as illustrated in Fig. 2, or such undulations may be produced by hanmering the thinner portion of the saw, care being taken that the convex portions of the undulations do not extend beyond the plane of the sur'- face of the saw at either side, and it is gen erally preferable to have these undulations uniform all around the saw; but such undulations may alternate, the convex portions on one side being between the concave portion at that side, the conveX portion projecting at the other side, thereby balancing and unifying the elasticity of-the saw in the direction of the radii, so that the middle portions of the saw may be expanded by the tension of the outer portions of the saw if the same becomes heated and so increased in size, and-the resiliency of the metal will cause the inner and thinner portions of the saw to contract as the rim may become smaller -when the temperature is reduced.

The teeth of the saw are to be made of any desired character and may be either integral with the saw-plate or separate, as both forms of teeth are well known, and the shape of the cutting edges of the teeth may also be Varied as occasion requires; but in the throat portion ofeach tooth or of any desired number of teeth around the saw recesses are made for the reception of the detachable throat-pieces B. These detachable throat-pieces are made as arcs of circles or ellipses with inclined ends, and these set into corresponding recesses, and one end 10 of each detachable throat-piece is V-shaped to set into a corresponding end portion of the recess either in the saw-plate or the ordinary detachable throat-plate, and at the end ll a rivet is to be inserted, passing through a hole partly in the detachable throatpiece and partly in the saw-plate or throatplate,so as to hold the detachable throat-piece firmly in position, and a second rivet at 12 is usually employed to insu re the stability of the detachable throat-piece.

The concave surface of the throat-piece is grooved advantageously with inclined sides and a flat bottom to the groove, as shown in Fig. 4. Thereby cutting edges 13 are formed upon the concave side of the detachable i throatpiece, and these detachable throat- Ic o 2 &16,373

pieoes can be made of tool-steel, so as to be sharpened and 'etain their cu tting edges, and the outer sui-faces of the detachable throatpieees should be slightlybeveled, so that the eutting edges 13 will be the widest portions of the detaehable throat-pieces.

In praetieal use it is found that almost all circular saws leave ridges to a greater or less extent upon the sui-faces of the Wood at the sides of the saw-kerf, and these detaehable throat-pieces become smoothing-cutters for removing such ridges and planing the surfaces of the Wood at the kerf, thereby leaving the sui-faces sawed in a smooth or planed condition, and, as these detachable throat-pieees cnt at eaeh side of the kerf, there is no tendeney to loosen snoh detaohable throat-pieees or to produce frietion upon the saw, and the saw Will run straight even When ripping crooked timber. I also prefer to groove the edges of the saw-plate to the rearof each ent-' ting point or tooth, as shown at 14, the object of such groove being to lessen the risk of the sawdust passing down between the sides of the saw and the sides of the kerf, the sawdust aecumulating in such grooves let and being thrown off eentrifugally and perpherally as soon as the groove passes out of the wood that is being sawed, and I prefer to make such grooves of a shape eorrespondin g to the g'ooves in the detachable threat-piece&

It will be apparent that where the teeth are ,integral with the saw-plate, as represented,

the peripheral grooves 14: in the edge of the saw allow the eutting-points of the teeth to be wider than the thiekness ot' the saw, because the metal of the saw ean be easilyspread immediately at the entting ends of the teeth by a tool driven into the V-shaped groove of the saw, and in this manner a set can be made upon the saw-teeth from time to time, as required, so that the teeth cut akerf that is slightly wider than the thickness of the saw-plate.

I claim as my invention 1. A eireular-saw plate of uniforn thickness adjaeent to the eye and at the rim or near-ly so, and with the intermediate portion thinner and provided with undulations that form the thin portion of the saw into springs that allow the exterior of the saw to expand if it becomes warm without throwing the saw out of line, snbstantially as set forth.

2. A eireular-saw plate of uniform thiekness adjaeent to the eye and at the rim or nearly so, and with the intermediate portion thinner and provided with radial nndulations that form the thin portion of the saw into springs that allow the eXterior of the saw to expand if it becomes warm without throwing the saw out of line, snbstantially as set forth.

3. The eirenlar saw having recesses in the threats of the teeth and detaehable threatpieees inserted in the recesses and Secured therein, the eoncave sides of such throatpieees being grooved or ehanneled so that the edges of the detaehable throat-pieces become eutters for smoothing the sui-faces of the Wood at the kerf, substantially as set fortl.

Signed by me this 25th day of July, 1898.

DEWEY PHILLIPS.

XVitnesses:

HAROLD SERRELL, S. T. HAVILAND. 

